1. Field of the Invention
The present invention relates to improvements in a connector cover for a portable terminal, for use in covering an opening formed in a casing of the portable terminal corresponding to the arrangement position of a connector for external connection.
2. Related Art
As a connector cover for a portable terminal covering an opening formed in a casing of the portable terminal, one disclosed in Japanese Patent Application Laid-open No. 2003-258964 (FIGS. 3 and 4, hereinafter referred to as Patent Document 1) is well-known. Further, as a general technique for securing a detachable covering member to the main body, a mounting structure of a decorative panel disclosed in Japanese Patent Application Laid-open No. 2001-317774 (FIGS. 6, 7 and 8, hereinafter referred to as Patent Document 2), for example, is well-known.
FIG. 1 shows a conventional connector cover for a portable terminal disclosed in Patent Document 1 as an example showing a specific configuration thereof. FIG. 1 is a horizontal sectional view partially showing the periphery of the mounting position of the connector cover, in the state where a portable terminal such as a mobile phone, a PHS, or a palmtop computer is disposed normally, taken by a horizontal plane across the center part in the thickness direction thereof.
As shown in FIG. 1, a casing 100 of the portable terminal has an opening 102 formed corresponding to the arrangement position of a connector 101 for external connection built in the casing 100, and is adopted to enable a connector cover 103 for covering the opening 102 to be mounted detachably. Specifically, on both sides of the opening 102, holes 104 and 104 are perforated, into which columnar connecting parts 105 and 105 of the connector cover 103 are inserted and fitted, whereby the opening 102 of the casing 100 is covered with the connector cover 103.
The tip of each columnar connecting part 105 has a tapered, diameter enlarged portion 106 formed integrally, and has a deformation allowing groove 107 radially penetrating the tip of the columnar connecting part 105 including the diameter enlarged portion 106. By the deformation allowing groove 107, the diameter enlarged portion 106 is divided into plural pieces, and the approaching/separating operation performed between the pieces is allowed by the elastically deforming action of the columnar connecting part 105.
Accordingly, in the state of the connector cover 103 being removed, when the tips of the diameter enlarged portions 106 of the columnar connecting parts 105 are inserted into the holes 104 of the casing 100 from the outside, the tapered faces of the pieces of the diameter enlarged portions 106 divided by the deformation allowing grooves 107 slidingly contact the inner peripheral faces of the holes 104, and are pressed from the radially outside. Thereby, the pieces of the diameter enlarged portions 106 are approaching each other, so that the outer diameters of the tip portions of the columnar connecting parts 105 are reduced, whereby the columnar connecting parts 105 are allowed to enter into the holes 104. Upon the tips of the columnar connecting parts 105 having penetrated the holes 104, the diameter enlarged portions 106 are elastically returned to the original state so that the diameters become enlarged. This prevents unintentional detachment of the columnar connecting parts 105 from the holes 104.
As obvious from FIG. 1, the diameter enlarged portions 106 are only formed at the tips of the columnar connecting parts 105, whereby the connector cover 103 can approach/separate freely within a certain range with respect to the casing 100 even in the state of the connector cover 103 being applied to the casing 100. Therefore, if the casing 100 and the connector cover 103 are left in the state of allowing a gap between them, there is caused a problem of dust being entered inside the casing 100 from the opening 102.
Conventionally, in order to solve such a problem so as to keep the connector cover 103 at a completely closing position as shown in FIG. 1, fitting between the columnar connecting parts 105 and the holes 104 has been adjusted to be tight fitting, or the columnar connecting parts 105 have been formed to be slightly sloped so as to secure the fastening force between the base parts of the columnar connecting parts 105 and the holes 104. However, deformation and dimensional changes due to repetition of attaching/detaching operations of the connector cover 103 or secular change, for example, make the fastening force between the base parts of the columnar connecting parts 105 and the holes 104 insufficient. This causes such a shortcoming that the connector cover 103 cannot be kept at the completely closing position.
On the other hand, in a general mounting structure of a covering member as disclosed in Patent Document 2, a pawl is provided at the tip of an arm having a sufficient span, and the arm is flexed by elastic deformation to thereby engage the pawl at the tip with an object such as a stopper. This structure can cope with deformation and dimensional changes due to some abrasion or secular change. However, since the span of the arm must be set to have a sufficient length, this structure is not suitable for a small product such as a connector cover for a portable terminal.